Abstract: A first torque control proportional electromagnetic valve (37) is connected through a first torque control line (41) to a third pressure receiving chamber (32D) in a first torque control regulator (32). A second torque control proportional electromagnetic valve (38) is connected through a second torque control line (42) to a third pressure receiving chamber (35D) in a second torque control regulator (35). The first and second torque control proportional electromagnetic valves (37, 38) are controlled by a controller 47. A switching valve (48) is provided between the first torque control line (41) and the second torque control line (42). The switching valve (48) supplies an output pressure of the first torque control proportional electromagnetic valve (37) to the third pressure receiving chamber (35D) in the second torque control regulator (35) at the time of driving hydraulic motors (2B, 2C) for left side and right side traveling.

Abstract: In a work machine including a solenoid valve that generates a pilot pressure to drive a directional control valve with use of the delivery pressure of a pilot pump as a source pressure, a shut-off valve that shuts off a hydraulic operating fluid from the pilot pump to the solenoid valve, a first sensor that senses the amount of operation of an operation lever, and a second sensor that senses a state amount relating to operation of the solenoid valve, whether or not an abnormality of the second sensor exists is determined on the basis of a sensing signal of the second sensor. When it is determined that the second sensor is abnormal, on the basis of a sensing signal of the first sensor, an opening command is made to the shut-off valve if operation of the operation lever is sensed, and a closing command is made to the shut-off valve if the neutral state of the operation lever is sensed.

Abstract: Provided is a wheel loader capable of moving up a lift arm in a short time during excavation work. A wheel loader comprises a controller configured to control maximum traction force of the wheel loader and input torque of a working device hydraulic pump, and include a specific condition determination section configured to determine whether a specific condition for specifying excavation work is satisfied, an elapsed time measurement section configured to measure an elapsed time from start of the excavation work, and an input torque control section configured to limit the input torque to a first input torque value when the specific condition is satisfied and increase the input torque from the first input torque value when a second set time elapses from the elapse of a first set time.

Abstract: A work machine includes a controller (20) that performs an area restriction control for controlling at least one hydraulic cylinder (32a) of a plurality of hydraulic cylinders (32) in such a manner that a work device (400) is located on or on an upper side of an optionally set target surface (60) during operation of an operation lever (26). In the work machine, if a jack-up angle (?) as an inclination angle of a machine body (1A) relative to a ground is larger than a preset target value (?t), the controller, in performing the area restriction control, corrects the control of the at least one hydraulic cylinder (32a) in such a manner that the jack-up angle approaches the target value. The target value is set such as to vary according to posture of an arm (406).

Abstract: Provided is a construction machine capable of driving each hydraulic actuator at a suitable speed while suppressing delivery flow rate of a hydraulic pump, both at a single operation time of driving each hydraulic actuator respectively singularly and at a combined operation time of simultaneously driving a plurality of hydraulic actuators.

Abstract: A power regeneration system of a work vehicle includes: a first generator (12) and a second generator (31) that are driven by an engine (11); a first electric circuit (C1) for supplying electric power to traveling motors (10L, 10R); a second electric circuit (C2) for supplying electric power to an auxiliary device (35); a voltage step down converter (21) providing electric power from the first electric circuit to the second electric circuit; and a controller (51) that determines whether a travel mode of the work vehicle is a powering mode or a regeneration mode in order to control driving of the voltage step down converter. If the travel mode is the regeneration mode, the controller provides the regenerative power from the first electric circuit through the voltage step down converter to the second electric circuit, in order to drive the auxiliary device with the regenerative power.

Abstract: A urea water tank (11) is provided with a unit insertion opening (12H) that is disposed on a top surface part (12A) of a tank body (12) and opens more largely than an external dimension (D2) of a sensor unit (20), a sensor mounting member (16) that is disposed on the top surface part (12A) of the tank body (12) and closes the unit insertion opening (12H), and a filter which is formed as a tubular body to surround the sensor unit (20), and inserted in the unit insertion opening (12H) of the tank body (12) from a lower end (24A4)-side, and having an upper end (24A3) mounted on the top surface part (12A) of the tank body (12) by using the sensor mounting member (16).

Abstract: A work vehicle including a tank (31,131) formed so as to extend from a rear part of a vehicle body toward a center, wherein the tank includes: a first storage tank (32) located on the rear side of the vehicle body, and stores stored fluid (9); a second storage tank (34) located on a side close to the center in the front-rear direction of the vehicle body, and stores the fluid; a partition part (36) that separates the first storage tank and the second storage tank; a discharge member (49) that has a discharge opening (49a) extending and opened inside the second storage tank, and discharges, from the second storage tank, the fluid stored in the second storage tank; and a hollow tube member (60) that has a first end communicated with the first storage tank through the partition part so as to enable the stored fluid to flow, and a second end having a hollow tube opening (62) extending and opened toward the center of the vehicle body inside the second storage tank, wherein the hollow tube opening of the hollow tub

Abstract: To make it possible to prevent a decrease in work speed due to a decrease in the speed of a given actuator when an operator unintentionally performs a fine operation of the control lever of the other actuator in a state in which the given actuator is driven by the hydraulic fluid delivered from a plurality of pumps, a controller (41) sets, as a composite dead zone line serving as a boundary of a composite dead zone, a composite dead zone line such that as an operation amount in one direction of a control lever (12L) or (13L) of a control lever device (12) or (13) is increased, the width of the composite dead zone corresponding to an operation amount in the other direction of the control lever is widened, and corrects the operation amount in the other direction such that the demanded flow rate of an actuator increases from zero, when the control lever is operated in the other direction in a state in which the operation amount in the one direction of the control lever remains within a range of the composite dea

Abstract: A controller outputs a first velocity (first limiting velocity) as a limiting velocity for a boom cylinder when a boom lowering operation amount is smaller than a first operation amount, and outputs a second velocity when the boom lowering operation amount is equal to or larger than the first operation amount. The first velocity is set to decrease according to a decrease in a target surface distance. The second velocity is defined by a weighted average of the first velocity and a third velocity (second limiting velocity) set to change according to one of the target surface distance and the boom lowering operation amount of the operation device, and is set such that an increase in the boom lowering operation amount reduces a weight for the first velocity while increasing a weight for the third velocity.

Abstract: A work vehicle including: a drive device that has an internal combustion engine for driving a vehicle body; a first tank for storing fuel to be supplied to the internal combustion engine; and a second tank for storing fuel to be supplied to the internal combustion engine; wherein the first tank is disposed in front of or behind the drive device, and the second tank is disposed below the drive device so as to be separated from the first tank by a predetermined distance.

Abstract: There is provided a work machine that is capable of realizing operability and energy saving ability that are equivalent to those of work machines that have a joint line to be used during swinging/boom raising operation, without incorporating a joint line for supplying a pressurized fluid from a second pump to a bottom-side chamber of a boom cylinder. The controller is configured to compute a hypothetical flow rate representing a flow rate in a hypothetical joint line, compute a first pump provisional target flow rate on the basis of an operation amount of a boom operation device, compute a second pump provisional target flow rate on the basis of an operation amount of a swing operation device, compute a first pump final target flow rate by adding the hypothetical flow rate to the first pump provisional target flow rate, and compute a second pump final target flow rate by subtracting the hypothetical flow rate from the second pump provisional target flow rate.

Abstract: A work vehicle provided with a loading hydraulic circuit (A), including at least a main hydraulic pump (31), a lift arm cylinder (8) and a control valve (32), an auxiliary hydraulic pump (31), a negative parking brake device (PB), and a parking brake releasing hydraulic circuit (B2), in which the vehicle includes: a loading operation hydraulic circuit (B1) located upstream of the parking brake releasing hydraulic circuit; an emergency flow path (80) for supplying the pressure oil discharged from the auxiliary hydraulic pump to the parking brake device through the loading operation hydraulic circuit in an emergency; and a valve unit (81) located in the emergency flow path. If the pressure of the parking brake releasing hydraulic circuit is lower than the brake release pressure to release the braking state of the parking brake device, the valve unit is switched to the communicating position.

Abstract: A controller 21 mounted on a work machine calculates a target carried load representing a target value for a carried load carried by the work machine on the basis of loadage of a transportation machine in case the loadage is changed, calculates a minimum integration load value depending on the magnitude of the calculated target carried load, and calculates the loadage by integrating the carried load in case it is determined that a work implement has performed a loading operation on the transportation machine and in case the calculated carried load is equal to or larger than the minimum integration load value.

Abstract: A hybrid work machine is configured with an engine 41, a hydraulic pump 51, a hydraulic actuator, a generator motor 61 coupled to the engine 41, an electric storage device 62 that transmits and receives electric power to and from the generator motor 61, an engine controller 42 that controls the engine 41 based on a target engine revolution speed, a power controller 63 that controls action of the generator motor 61, a controller 72 that controls the engine controller 42 and the power controller 63, and a target engine revolution speed change instructing device that give instructions on a change in the target engine revolution speed. The controller 72 controls the engine controller 42 and the power controller 63 to act the generator motor 61 as a generator until an actual revolution speed of the engine 41 is reduced to a revolution speed corresponding to a target engine revolution speed after change if the target engine revolution speed has been changed to be lower while the engine 41 is in an unloaded state.

Abstract: A loading amount accumulation device includes a loading amount storage section 403 storing a loading amount, a loading amount calculation section 402 accumulating load weight data about a transport object in a working front to the loading amount, and updating the loading amount by the value after being accumulated, a difference calculation section 404 calculating a difference between a loaded amount of a vessel and the loading amount, an accumulation success/failure determination section 405 comparing an absolute value of the difference and a value Dth, determining that accumulation has failed when the absolute value is larger than the value Dth, and outputting a result, a loading amount correction section 406, when the failure is output as the result, performing correction so as to set the loaded amount data as the loading amount, and updating the loading amount by the corrected loading amount, and an output section outputting the loading amount.

Abstract: A reversing assistance device suited for a mining dump truck measures a first distance to a first object, which exists at a first height comprising a trajectory of a rear wheel of the dump truck during reversing, and a second distance to a second object, which exists at a second height comprising a trajectory of a vessel during the reversing, for computing the position of the first object. If the distance between the position of the first object and a designated loading position designated by an operator of a loading machine is equal to or smaller than a threshold, the first object is determined to be an approachable object, a smaller one of the first distance and the second distance is determined as a target stop distance, and based on the target stop distance, a target stop position is computed.

Abstract: In an unloaded state of the bucket (3), a control device (30) calculates an unloaded moment (M0) around a hinge pin G from the pressure of the lift arm cylinder that is detected by pressure sensors (15a, 15b), the angle of a lift arm that is detected by a lift arm angle sensor 14, and dimension data extracted from a vehicle body information database (35). In a loaded state of the bucket, the control device calculates a loaded moment (M1) around the hinge pin G from the pressure of the lift arm cylinder, the angle of the lift arm, and the dimension data extracted from the vehicle body information database. The control device calculates the load (W) on the bucket by dividing the difference between the unloaded moment and the loaded moment by the horizontal distance (Lw) between the hinge pin and the gravity center position of the bucket.

Abstract: Provided is a loading vehicle in which a control characteristic of traction force can be easily and finely set and changed while a configuration of a hydraulic circuit is simple. An HST traveling driven wheel loader includes an electronically controlled HST pump and HST motor, including a solenoid proportional pressure reducing valve to control displacement volume of the HST pump based on a control signal output from a controller. The controller stores characteristic tables indicating a correlation between discharge pressure of a loading hydraulic pump or an operation state of an engine and a maximum discharge pressure of the HST pump, and when the vehicle speed corresponds to work requiring traction force, outputs a control signal to the solenoid proportional pressure reducing valve so as to obtain the maximum discharge pressure Pm of the HST pump that corresponds to one of the characteristic tables.

Abstract: A traveling device (11) is provided with an electric motor (16) provided in a vehicle body (2) of a dump truck (1), an output shaft (17) an axial base end of which is connected to the electric motor (16) and which outputs rotation of the electric motor (16), a bottomed hole spline (53) formed in an axial front end of the output shaft (17), and an input shaft (42) which has a shaft spline (54) spline-coupled to the hole spline (53), and inputs the rotation of the output shaft (17) to a reduction gear mechanism (27). The output shaft (17) is provided with an oil reservoir space (55) formed in the innermost part of the hole spline (53), an annular oil groove (56) and an oil path (57) providing communication between the oil reservoir space (55) and the annual oil groove (56).